The present invention relates generally to a method of coating and curing peroxide-curable coatings in-line on polymer film, and the film produced thereby. More particularly, the present invention is directed to a commercially viable process for producing a coated polymer film having various beneficial properties through in-line coating and peroxide curing steps utilizing a melamine crosslinker.
Polymer film can be modified in various ways to enhance its usefulness for specific applications. Coatings applied to one or both surfaces of the film are commonly used to achieve such modification. Various qualities such as adhesion, smoothness, oxygen permeability, printability, opacity, scratch resistance and the like can be altered through the judicious use of coating technology. Among such coatings, peroxide curable coatings are known. These coatings are typically cured by the in situ polymerization of appropriate monomers and oligomers. Most known curable coatings are applied to film off-line, after the film has been oriented, set and cooled, but the thermal activation and cure required for peroxide curable coatings has generally rendered off-line coating problematic. On the other hand, in-line coating of peroxide curable coatings has generally been considered of limited feasibility.